"Precautionary measures were taken. There was no threat to the President or his family," the official told the traveling press corps.
The pilot mistakenly entered the area at about 1 p.m. Saturday, June 5 after he failed to download updated flight restrictions, said Anthony Guglielmi, a spokesman for the US Secret Service. A fighter jet then made visual contact with the plane and escorted it to Cape May Airport in Lower Township.
"Preliminary investigation reveals the pilot was not on the proper radio channel, was not following the NOTAMS (Notice to Airmen) that had been filed and was not following published flight guidance," Guglielmi said in a statement.
Guglielmi said Biden and his wife were moved as a precaution and safety returned to the house, where they spent the weekend.
Click here to follow Daily Voice Mahwah-Ramsey and receive free news updates.